Wireless products are utilized in a variety of environments such as mobile (for example cellular and Wi-Fi for handsets) or non-mobile (for example Wi-Fi for access points and routers). A voltage-controlled oscillator or VCO is an electronic oscillator whose oscillation frequency is controlled by a voltage input. The applied input voltage determines the instantaneous oscillation frequency. Consequently, modulating signals applied to control input may cause frequency modulation (FM) or phase modulation (PM). A VCO may also be part of a phase-locked loop. The VCO may be utilized in amplifiers in such products to amplify the signals received or transmitted therefrom. As the market for wireless products develops there becomes an ever increasing need for more bandwidth and more data across mobile and non-mobile networks with more demand for higher efficiency and linearity. Therefore the communication of such data over these networks is becoming more and more difficult. For example, as the bandwidth goes up as network evolves, and at the same time the signals consolations become more dense such as 802.11ax standard for WiFi application. As a result, in-band and out of band noise of VCO becomes extremely important. Also VCO pulling is a major issue. This case is more critical in a presence of a high power amplifier for integration. In addition, traditional VCO architectures rely on a buffer to center output of core VCO before driving the inverter chain following the core. This buffer consumes major power and is another source of noise and disturbance issue.
VCO tuning range is another issue. VCO tuning range is limited due to noise of capacitor banks and its parasitics.
Devices and circuits in accordance with the present invention address such a needs.